/*
 * Algorithm info parsing and creation functions
 * Author: JuanJo Ciarlante <jjo-ipsec@mendoza.gov.ar>
 *
 * alg_info.h,v 1.1.2.1 2003/11/21 18:12:23 jjo Exp
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 */

#ifndef ALG_INFO_H
#define ALG_INFO_H

#include "constants.h"

/*	
 *	Creates a new alg_info by parsing passed string		
 */
enum parser_state_esp {
        ST_INI,         /* parse esp= string */
	ST_INI_AA,      /* parse ah= string */
	ST_EA,		/* encrypt algo   */
	ST_EA_END,	
	ST_EK,		/* enc. key length */
	ST_EK_END,
	ST_AA,		/* auth algo */
	ST_AA_END,
	ST_AK,		/* auth. key length */
	ST_AK_END,
	ST_MODP,	/* modp spec */
	ST_END,
	ST_EOF,
	ST_ERR
};

/* XXX:jjo to implement different parser for ESP and IKE */
struct parser_context {
	unsigned state, old_state;
	unsigned protoid;
	char ealg_buf[16];
	char aalg_buf[16];
	char modp_buf[16];
	int (*ealg_getbyname)(const char *const str, int len);
	int (*aalg_getbyname)(const char *const str, int len);
	int (*modp_getbyname)(const char *const str, int len);
	char *ealg_str;
	char *aalg_str;
	char *modp_str;
	int eklen;
	int aklen;
    bool ealg_permit;
    bool aalg_permit;
	int ch;
	const char *err;
};

struct esp_info {
        bool     esp_default; 
	u_int8_t transid;	/* ESP transform (AES, 3DES, etc.)*/
	u_int16_t auth;		/* AUTH */
	u_int32_t enckeylen;	/* keylength for ESP transform (bytes)*/
	u_int32_t authkeylen;	/* keylength for AUTH (bytes)*/
	u_int8_t encryptalg;	/* normally  encryptalg=transid */
	u_int16_t authalg;	/* normally  authalg=auth+1
				 * Paul: apparently related to magic at
				 * lib/libswan/alg_info.c alg_info_esp_aa2sadb() */
};

struct ike_info {
    bool      ike_default;
    u_int16_t ike_ealg;	  /* encrytion algorithm - bit 15set for reserved*/
    u_int8_t  ike_halg;   /* hash algorithm */
    size_t    ike_eklen;     /* how many bits required by encryption algo */
    size_t    ike_hklen;     /* how many bits required by hash algo */
    oakley_group_t ike_modp;  /* which modp group to use */
};

#define ALG_INFO_COMMON \
	int alg_info_cnt;		\
	int ref_cnt;			\
	unsigned alg_info_protoid

struct alg_info {
	ALG_INFO_COMMON;
};

struct alg_info_esp {
	ALG_INFO_COMMON;
	struct esp_info esp[128];
	int esp_pfsgroup;
};

struct alg_info_ike {
	ALG_INFO_COMMON;
	struct ike_info ike[128];
};

#define ESPTOINFO(X) (struct alg_info *)X
#define IKETOINFO(X) (struct alg_info *)X


#define esp_ealg_id transid
#define esp_aalg_id auth
#define esp_ealg_keylen enckeylen	/* bits */
#define esp_aalg_keylen authkeylen	/* bits */

extern enum ipsec_authentication_algo
alg_info_esp_aa2sadb(enum ikev1_auth_attribute auth);
int alg_info_esp_sadb2aa(int sadb_aalg);
enum ikev1_auth_attribute
alg_info_esp_v2tov1aa(enum ikev2_trans_type_integ ti);

void alg_info_free(struct alg_info *alg_info);
void alg_info_addref(struct alg_info *alg_info);
void alg_info_delref(struct alg_info **alg_info);
struct alg_info_esp * alg_info_esp_create_from_str(const char *alg_str
						   , err_t *err_p
						   , bool permitmann);

struct alg_info_esp * alg_info_ah_create_from_str(const char *alg_str
						  , err_t *err_p
						  , bool permitmann);

struct alg_info_ike * alg_info_ike_create_from_str(const char *alg_str
						   , err_t *err_p);

int alg_info_parse(const char *str);
int alg_info_snprint(char *buf, int buflen
		     , struct alg_info *alg_info, bool permitike);

void alg_info_snprint_ike(char *buf, size_t buflen, struct alg_info_ike *alg_info);
#define ALG_INFO_ESP_FOREACH(ai, ai_esp, i) \
	for (i=(ai)->alg_info_cnt,ai_esp=(ai)->esp; i--; ai_esp++) 
#define ALG_INFO_IKE_FOREACH(ai, ai_ike, i) \
	for (i=(ai)->alg_info_cnt,ai_ike=(ai)->ike; i--; ai_ike++) 

extern int alg_enum_search_prefix (enum_names *ed, const char *prefix, const char *str, int str_len);
extern int alg_enum_search_ppfix (enum_names *ed, const char *prefix
				  , const char *postfix, const char *str
				  , int str_len);

struct parser_context;
struct oakley_group_desc;
extern int alg_info_parse_str (struct alg_info *alg_info
			       , const char *alg_str
			       , const char **err_p
			       , void (*parser_init)(struct parser_context *p_ctx)
			       , void (*alg_info_add)(struct alg_info *alg_info
						      , int ealg_id, int ek_bits
						      , int aalg_id, int ak_bits
						      , int modp_id
						      , bool permitmann)
			       , const struct oakley_group_desc *(*lookup_group_f)(u_int16_t group)
			       , bool permitmann);

#endif /* ALG_INFO_H */

/*
 * Local Variables:
 * c-basic-offset:4
 * c-style: pluto
 * End:
 */
